From Linux NFS
A Namespace Database, or NSDB, is the repository for fileset location information in a FedFS domain. At its core, an NSDB is simply an LDAP server with an NSDB Container Entry, or NCE, for short. FedFS data is stored as children of this entry.
In this article, we introduce several simple command line tools that can be used to manage and troubleshoot an NSDB.
First, create an entry for your NSDB in your admin host's NSDB connection parameters database. Support your NSDB can be contacted at ldap.example.net:389, and the distinguished name of the NSDB Container Entry is "ou=fedfs,dc=example,dc=net". Then:
# nsdbparams update -D cn=Manager -e ou=fedfs,dc=example,dc=net ldap.example.net
The NSDB hostname and port are almost always a parameter of each NSDB admin tool. To save yourself some typing, you can set up environment variables containing the hostname and port of the NSDB you'll be working with.
$ export FEDFS_NSDB_HOST="ldap.example.net"
By default, the standard LDAP port is assumed, so nothing else needs to be done. But if your NSDB uses port 636, for example, you could use something like this:
$ export FEDFS_NSDB_PORT=636
Now, assuming you've already configured it, see if your NSDB is listening:
This command should tell you which naming contexts on your NSDB host an NSDB Container Entry. You should see the NCE you may have created earlier with the nsdb-simple-nces command. There are probably no FedFS records yet, but you can confirm that with:
The "nsdb-list" command displays a list of Fileset Names (FSNs). These represent filesets. Each replica of a fileset is represented by the children FSLs also listed.
You can examine one FSN more closely by copying its UUID from this list and using it as an argument of the "nsdb-resolve-fsn" command. For example:
$ nsdb-resolve-fsn b0f5d578-1e13-11e2-a64a-000c296d4dd3
You can adjust the information in the children FSLs using the "nsdb-update-fsl" command. See its man page for details.